From: Christoph Hellwig Date: Tue, 8 Apr 2025 07:05:47 +0000 (+0200) Subject: xfs: make metabtree reservations global X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=18c62f4433ec59368e489047f35d25a74bb04eb3;p=users%2Fhch%2Fxfsprogs.git xfs: make metabtree reservations global Source kernel commit: 1df8d75030b787a9fae270b59b93eef809dd2011 Currently each metabtree inode has it's own space reservation to ensure it can be expanded to the maximum size, mirroring what is done for the AG-based btrees. But unlike the AG-based btrees the metabtree inodes aren't restricted to allocate from a single AG but can use free space form the entire file system. And unlike AG-based btrees where the required reservation shrinks with the available free space due to this, the metabtree reservations for the rtrmap and rtfreflink trees are not bound in any way by the data device free space as they track RT extent allocations. This is not very efficient as it requires a large number of blocks to be set aside that can't be used at all by other btrees. Switch to a model that uses a global pool instead in preparation for reducing the amount of reserved space, which now also removes the overloading of the i_nblocks field for metabtree inodes, which would create problems if metabtree inodes ever had a big enough xattr fork to require xattr blocks outside the inode. Signed-off-by: Christoph Hellwig Reviewed-by: "Darrick J. Wong" Signed-off-by: Christoph Hellwig --- diff --git a/libxfs/xfs_metafile.c b/libxfs/xfs_metafile.c index 767326551..1216a0e51 100644 --- a/libxfs/xfs_metafile.c +++ b/libxfs/xfs_metafile.c @@ -19,6 +19,9 @@ #include "xfs_inode.h" #include "xfs_errortag.h" #include "xfs_alloc.h" +#include "xfs_rtgroup.h" +#include "xfs_rtrmap_btree.h" +#include "xfs_rtrefcount_btree.h" static const struct { enum xfs_metafile_type mtype; @@ -72,12 +75,11 @@ xfs_metafile_clear_iflag( } /* - * Is the amount of space that could be allocated towards a given metadata - * file at or beneath a certain threshold? + * Is the metafile reservations at or beneath a certain threshold? */ static inline bool xfs_metafile_resv_can_cover( - struct xfs_inode *ip, + struct xfs_mount *mp, int64_t rhs) { /* @@ -86,43 +88,38 @@ xfs_metafile_resv_can_cover( * global free block count. Take care of the first case to avoid * touching the per-cpu counter. */ - if (ip->i_delayed_blks >= rhs) + if (mp->m_metafile_resv_avail >= rhs) return true; /* * There aren't enough blocks left in the inode's reservation, but it * isn't critical unless there also isn't enough free space. */ - return xfs_compare_freecounter(ip->i_mount, XC_FREE_BLOCKS, - rhs - ip->i_delayed_blks, 2048) >= 0; + return xfs_compare_freecounter(mp, XC_FREE_BLOCKS, + rhs - mp->m_metafile_resv_avail, 2048) >= 0; } /* - * Is this metadata file critically low on blocks? For now we'll define that - * as the number of blocks we can get our hands on being less than 10% of what - * we reserved or less than some arbitrary number (maximum btree height). + * Is the metafile reservation critically low on blocks? For now we'll define + * that as the number of blocks we can get our hands on being less than 10% of + * what we reserved or less than some arbitrary number (maximum btree height). */ bool xfs_metafile_resv_critical( - struct xfs_inode *ip) + struct xfs_mount *mp) { - uint64_t asked_low_water; + ASSERT(xfs_has_metadir(mp)); - if (!ip) - return false; - - ASSERT(xfs_is_metadir_inode(ip)); - trace_xfs_metafile_resv_critical(ip, 0); + trace_xfs_metafile_resv_critical(mp, 0); - if (!xfs_metafile_resv_can_cover(ip, ip->i_mount->m_rtbtree_maxlevels)) + if (!xfs_metafile_resv_can_cover(mp, mp->m_rtbtree_maxlevels)) return true; - asked_low_water = div_u64(ip->i_meta_resv_asked, 10); - if (!xfs_metafile_resv_can_cover(ip, asked_low_water)) + if (!xfs_metafile_resv_can_cover(mp, + div_u64(mp->m_metafile_resv_target, 10))) return true; - return XFS_TEST_ERROR(false, ip->i_mount, - XFS_ERRTAG_METAFILE_RESV_CRITICAL); + return XFS_TEST_ERROR(false, mp, XFS_ERRTAG_METAFILE_RESV_CRITICAL); } /* Allocate a block from the metadata file's reservation. */ @@ -131,22 +128,24 @@ xfs_metafile_resv_alloc_space( struct xfs_inode *ip, struct xfs_alloc_arg *args) { + struct xfs_mount *mp = ip->i_mount; int64_t len = args->len; ASSERT(xfs_is_metadir_inode(ip)); ASSERT(args->resv == XFS_AG_RESV_METAFILE); - trace_xfs_metafile_resv_alloc_space(ip, args->len); + trace_xfs_metafile_resv_alloc_space(mp, args->len); /* * Allocate the blocks from the metadata inode's block reservation * and update the ondisk sb counter. */ - if (ip->i_delayed_blks > 0) { + mutex_lock(&mp->m_metafile_resv_lock); + if (mp->m_metafile_resv_avail > 0) { int64_t from_resv; - from_resv = min_t(int64_t, len, ip->i_delayed_blks); - ip->i_delayed_blks -= from_resv; + from_resv = min_t(int64_t, len, mp->m_metafile_resv_avail); + mp->m_metafile_resv_avail -= from_resv; xfs_mod_delalloc(ip, 0, -from_resv); xfs_trans_mod_sb(args->tp, XFS_TRANS_SB_RES_FDBLOCKS, -from_resv); @@ -173,6 +172,9 @@ xfs_metafile_resv_alloc_space( xfs_trans_mod_sb(args->tp, field, -len); } + mp->m_metafile_resv_used += args->len; + mutex_unlock(&mp->m_metafile_resv_lock); + ip->i_nblocks += args->len; xfs_trans_log_inode(args->tp, ip, XFS_ILOG_CORE); } @@ -184,26 +186,33 @@ xfs_metafile_resv_free_space( struct xfs_trans *tp, xfs_filblks_t len) { + struct xfs_mount *mp = ip->i_mount; int64_t to_resv; ASSERT(xfs_is_metadir_inode(ip)); - trace_xfs_metafile_resv_free_space(ip, len); + + trace_xfs_metafile_resv_free_space(mp, len); ip->i_nblocks -= len; xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); + mutex_lock(&mp->m_metafile_resv_lock); + mp->m_metafile_resv_used -= len; + /* * Add the freed blocks back into the inode's delalloc reservation * until it reaches the maximum size. Update the ondisk fdblocks only. */ - to_resv = ip->i_meta_resv_asked - (ip->i_nblocks + ip->i_delayed_blks); + to_resv = mp->m_metafile_resv_target - + (mp->m_metafile_resv_used + mp->m_metafile_resv_avail); if (to_resv > 0) { to_resv = min_t(int64_t, to_resv, len); - ip->i_delayed_blks += to_resv; + mp->m_metafile_resv_avail += to_resv; xfs_mod_delalloc(ip, 0, to_resv); xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FDBLOCKS, to_resv); len -= to_resv; } + mutex_unlock(&mp->m_metafile_resv_lock); /* * Everything else goes back to the filesystem, so update the in-core @@ -213,61 +222,96 @@ xfs_metafile_resv_free_space( xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, len); } -/* Release a metadata file's space reservation. */ +static void +__xfs_metafile_resv_free( + struct xfs_mount *mp) +{ + if (mp->m_metafile_resv_avail) { + xfs_mod_sb_delalloc(mp, -(int64_t)mp->m_metafile_resv_avail); + xfs_add_fdblocks(mp, mp->m_metafile_resv_avail); + } + mp->m_metafile_resv_avail = 0; + mp->m_metafile_resv_used = 0; + mp->m_metafile_resv_target = 0; +} + +/* Release unused metafile space reservation. */ void xfs_metafile_resv_free( - struct xfs_inode *ip) + struct xfs_mount *mp) { - /* Non-btree metadata inodes don't need space reservations. */ - if (!ip || !ip->i_meta_resv_asked) + if (!xfs_has_metadir(mp)) return; - ASSERT(xfs_is_metadir_inode(ip)); - trace_xfs_metafile_resv_free(ip, 0); + trace_xfs_metafile_resv_free(mp, 0); - if (ip->i_delayed_blks) { - xfs_mod_delalloc(ip, 0, -ip->i_delayed_blks); - xfs_add_fdblocks(ip->i_mount, ip->i_delayed_blks); - ip->i_delayed_blks = 0; - } - ip->i_meta_resv_asked = 0; + mutex_lock(&mp->m_metafile_resv_lock); + __xfs_metafile_resv_free(mp); + mutex_unlock(&mp->m_metafile_resv_lock); } -/* Set up a metadata file's space reservation. */ +/* Set up a metafile space reservation. */ int xfs_metafile_resv_init( - struct xfs_inode *ip, - xfs_filblks_t ask) + struct xfs_mount *mp) { + struct xfs_rtgroup *rtg = NULL; + xfs_filblks_t used = 0, target = 0; xfs_filblks_t hidden_space; - xfs_filblks_t used; - int error; + int error = 0; - if (!ip || ip->i_meta_resv_asked > 0) + if (!xfs_has_metadir(mp)) return 0; - ASSERT(xfs_is_metadir_inode(ip)); + /* + * Free any previous reservation to have a clean slate. + */ + mutex_lock(&mp->m_metafile_resv_lock); + __xfs_metafile_resv_free(mp); + + /* + * Currently the only btree metafiles that require reservations are the + * rtrmap and the rtrefcount. Anything new will have to be added here + * as well. + */ + while ((rtg = xfs_rtgroup_next(mp, rtg))) { + if (xfs_has_rtrmapbt(mp)) { + used += rtg_rmap(rtg)->i_nblocks; + target += xfs_rtrmapbt_calc_reserves(mp); + } + if (xfs_has_rtreflink(mp)) { + used += rtg_refcount(rtg)->i_nblocks; + target += xfs_rtrefcountbt_calc_reserves(mp); + } + } + + if (!target) + goto out_unlock; /* - * Space taken by all other metadata btrees are accounted on-disk as + * Space taken by the per-AG metadata btrees are accounted on-disk as * used space. We therefore only hide the space that is reserved but * not used by the trees. */ - used = ip->i_nblocks; - if (used > ask) - ask = used; - hidden_space = ask - used; + if (used > target) + target = used; + hidden_space = target - used; - error = xfs_dec_fdblocks(ip->i_mount, hidden_space, true); + error = xfs_dec_fdblocks(mp, hidden_space, true); if (error) { - trace_xfs_metafile_resv_init_error(ip, error, _RET_IP_); - return error; + trace_xfs_metafile_resv_init_error(mp, 0); + goto out_unlock; } - xfs_mod_delalloc(ip, 0, hidden_space); - ip->i_delayed_blks = hidden_space; - ip->i_meta_resv_asked = ask; + xfs_mod_sb_delalloc(mp, hidden_space); + + mp->m_metafile_resv_target = target; + mp->m_metafile_resv_used = used; + mp->m_metafile_resv_avail = hidden_space; + + trace_xfs_metafile_resv_init(mp, target); - trace_xfs_metafile_resv_init(ip, ask); - return 0; +out_unlock: + mutex_unlock(&mp->m_metafile_resv_lock); + return error; } diff --git a/libxfs/xfs_metafile.h b/libxfs/xfs_metafile.h index 95af4b52e..ae6f9e779 100644 --- a/libxfs/xfs_metafile.h +++ b/libxfs/xfs_metafile.h @@ -26,13 +26,13 @@ void xfs_metafile_clear_iflag(struct xfs_trans *tp, struct xfs_inode *ip); /* Space reservations for metadata inodes. */ struct xfs_alloc_arg; -bool xfs_metafile_resv_critical(struct xfs_inode *ip); +bool xfs_metafile_resv_critical(struct xfs_mount *mp); void xfs_metafile_resv_alloc_space(struct xfs_inode *ip, struct xfs_alloc_arg *args); void xfs_metafile_resv_free_space(struct xfs_inode *ip, struct xfs_trans *tp, xfs_filblks_t len); -void xfs_metafile_resv_free(struct xfs_inode *ip); -int xfs_metafile_resv_init(struct xfs_inode *ip, xfs_filblks_t ask); +void xfs_metafile_resv_free(struct xfs_mount *mp); +int xfs_metafile_resv_init(struct xfs_mount *mp); /* Code specific to kernel/userspace; must be provided externally. */